why do plant roots grow downward?

Answer 1

Not all plant roots grow downward.

First, the roots grow down because it needs to search for water, it's also good for anchoring the plant.

But in the case of some places like Louisiana, water doesn't go deep into the ground, which causes the plants to have short roots.

A tree fell on my home after Rita. It was a very large tree with very short roots because the tree didn't need long roots to find water. So, the tree didn't have a good anchor.

Answer 2

The plant hormone called auxin makes roots grow downward.

Answer 3

They grow downward because of the root cap in the root tip. The root cap is a thimble shaped protective layer of tissue that is notable for its apogeotropism or it is known for being positively geotrophic. It is made up of peripheral cells and columella cells. The shape itself, columnar, makes it grow downward. Another thing, the root cap is starchy and also secretes mucilage, making it heavy and grow downward. The mucilage it secretes serves as protection from insects and it also lubricates the root.

Hope that helps. :-)

Answer 4

so they can build a support system for the plant which grows upward. No roots and it would just topple over. Also the deeper the roots, the more water they are able to have access to.

Answer 5

Roots have small starch grains (stratoliths) that sense gravity. They are made to respond to this by growing down at all times (even if turned). Roots would not be too useful in the air.

Answer 6

There is something that makes them do it, but I can't remember what. It has to be gravity influenced.

Try looking under "plant trophisms".

Answer 7

to gain a foothold for stability and also for nutrients and water .its more down and out to cover a large area under them